June 21 Holidays, events and History 2021.
| Date | Day | Holiday Name | Holiday Type | Country |
| 21 Jun | Monday | Aymara New Year Day | National holiday | Bolivia |
| 21 Jun | Monday | June Solstice | Season | Nepal |
| 21 Jun | Monday | National Heroes Day | Public Holiday | Bermuda |
| 21 Jun | Monday | Queen’s Birthday | Public Holiday | Cayman Islands |
| 21 Jun | Monday | Orthodox Pentecost Monday | National holiday, Orthodox | Cyprus |
| 21 Jun | Monday | Queen’s Birthday | Public Holiday | Gibraitar |
| 21 Jun | Monday | Orthodox Holy Spirit Monday | De facto holiday | Greece |
| 21 Jun | Monday | National Day | Public Holiday | Greenland |
| 21 Jun | Monday | Orthodox Pentecost Monday | National holiday, Orthodox | Romania |
| 21 Jun | Monday | Orthodox Pentecost holiday | National holiday, Orthodox | Ukraine |